Anna Kournikova was flashing a sizable diamond ring on her left hand at last night’s World Team Tennis match in King of Prussia, Pa. But the tennis cutie — who’s been linked to singer Enrique Iglesias — deflected questions about the rock’s sig nificance. “I thought you were the good press,” she purred to an Associated Press interrogator. The former Grand Slam doubles champ then whipped her hand behind her back and didn’t elaborate.